The patent incorporated by reference shows a disk type signal recorder operable in a superconductive environment. The disk includes superconductive materials for storing information bearing signals and is read or sensed using Superconducting Quantum Interference Devices (SQUIDS), a known form of junction devices in superconductive materials. The signals may be recorded using the known longitudinal recording techniques in a spinning signal storing disk. Longitudinal recording has magnetic flux aligned with the surface of the signal-storing member; i.e. the magnetic dipole is parallel to the surface of the disk. In the case of a superconductor, a circulating current induces the magnetic flux. Another type of magnetic recording is the so-called vertical recording wherein the magnetic dipole is perpendicular to the surface of the surface in a signal-storing member. The present invention uses vertical recording techniques.
Type II superconductors, used in the present invention, include materials in the perovskite class of materials. It is known that so-called vortices can be induced in these materials. The vortex can be created by a vertical magnetic field penetrating into a sheet of perovskite material from a recording surface to induce a circulating electrical current in the sheet of material (the current forms a circle when viewed into the recording surface of the material). The circulating electrical current then maintains a magnetic dipole perpendicular to the plane of the materials. A vertically flowing magnetic flux in a sheet Type II superconductor creates a circulating current in the plane of sheet. The directional sense of the circulating electrical current depends on the direction of the vortex-inducing magnetic flux and becomes indicative of the information bit stored in the created vortex. A clockwise circulating current, which maintains a magnetic dipole having a first magnetic orientation (when the circulating current is in a horizontal plane, the north pole of the dipole points downwardly), indicates a first binary state while a counter-clockwise current flow maintains an oppositely poled magnetic dipole to indicate a second binary state. Either binary state can be denoted as a one or zero. So long as the perovskite material is in a superconductive state (type II superconductor), the electrical current flows with essentially no electrical impedance for maintaining a magnetic flux which flows through the center of the vortex perpendicular to the surface of the superconductive recording material.
Each vortex has a constant amount of magnetic flux (quantum of magnetic flux) equal to the quotient of Planck's constant "h" divided by twice the electrical charge value "e". This value is about 2.multidot.10.sup.-15 gauss. A superconducting vortex is a true digital or a minimal discrete value for storing one bit of information.